U.S. patent number 4,601,845 [Application Number 06/719,095] was granted by the patent office on 1986-07-22 for bleaching compositions containing mixed metal cations adsorbed onto aluminosilicate support materials.
This patent grant is currently assigned to Lever Brothers Company. Invention is credited to James S. Namnath.
United States Patent |
4,601,845 |
Namnath |
* July 22, 1986 |
Bleaching compositions containing mixed metal cations adsorbed onto
aluminosilicate support materials
Abstract
A bleaching composition is provided comprising a peroxy compound
and a peroxide catalyst. The catalyst is an aluminosilicate,
perferably a zeolite, whereon is adsorbed a water-soluble manganese
(II) salt and magnesium or zinc divalent cations.
Inventors: |
Namnath; James S. (Demarest,
NJ) |
Assignee: |
Lever Brothers Company (New
York, NY)
|
[*] Notice: |
The portion of the term of this patent
subsequent to August 20, 2002 has been disclaimed. |
Family
ID: |
24888731 |
Appl.
No.: |
06/719,095 |
Filed: |
April 2, 1985 |
Current U.S.
Class: |
510/311;
252/186.3; 510/376; 510/507; 8/107; 252/186.38 |
Current CPC
Class: |
C11D
3/3935 (20130101); C11D 3/3932 (20130101) |
Current International
Class: |
C11D
3/39 (20060101); C11D 003/06 (); C11D 003/39 ();
D06L 003/02 () |
Field of
Search: |
;252/94,95,99,186.38,174.25 ;8/107 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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25608 |
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Mar 1981 |
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EP |
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70079 |
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Jul 1982 |
|
EP |
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72166 |
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Feb 1983 |
|
EP |
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82563 |
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Jun 1983 |
|
EP |
|
Other References
"Transition Metal Ions on Molecular Sieves. II. Catalytic
Activities of Transition Metal Ions on Molecular Sieves For the
Decomposition of Hydrogen Peroxide", by Mochida et al., J. Phys.
Chem., 78, pp. 1653-1657 (1974)..
|
Primary Examiner: Willis; Prince E.
Attorney, Agent or Firm: Honig; Milton L. Farrell; James
J.
Claims
What is claimed is:
1. A bleaching composition comprising:
(a) a peroxy compound; and
(b) a bleach catalyst comprising an aluminosilicate support
material whereon is adsorbed a water-soluble manganese (II) salt
and a salt of a divalent metal cation selected from magnesium or
zinc;
the weight ratio of manganese (II) to divalent metal cation being
from about 1:20 to 20:1, the ratio of divalent metal cation to
aluminosilicate support material ranging from about 1:1000 to 1:10,
and the weight ratio of catalyst to peroxy compound being from
about 1:100 to 1:1.
2. A bleaching composition according to claim 1 wherein the
aluminosilicate support material is a zeolite.
3. A bleaching composition according to claim 1 wherein the
aluminosilicate support material has a pore size from about 3 to 10
Angstroms.
4. A bleaching composition according to claim 1 wherein the
aluminosilicate support material is silicoalumino phosphate.
5. A bleaching composition according to claim 1 wherein the peroxy
compound is sodium perborate.
6. A bleaching composition according to claim 1 further comprising
an inorganic phosphate salt stabilizer in an amount from about 5 to
35% by weight of the total composition.
7. A bleaching composition according to claim 6 wherein the
phosphate stabilizer is chosen from the group consisting of
tripolyphosphate, orthophosphate, pyrophosphate and mixtures
thereof.
8. A bleaching composition according to claim 1 further comprising
from 1 to 98% of laundry detergent adjuncts selected from the group
consisting of surfactants, builders, fabric softeners, enzymes,
inorganic fillers, colorants, lather boosters and mixtures
thereof.
9. A process for preparation of a catalyst for the controlled
decomposition of peroxy compounds comprising:
(a) dissolving a water-soluble salt of manganese (II) and of a
divalent metal cation selected from magnesium or zinc, in a solvent
and therein suspending an aluminosilicate support material to form
a slurry, the weight ratio of divalent metal cation to the
aluminosilicate ranging from 1:1000 to 1:10 and of manganese (II)
to divalent metal cation ranging from about 1:20 to 20:1;
(b) adjusting pH to achieve a value from about 7.0 to 11.1;
(c) agitating the slurry mixture of divalent metal salt and
aluminosilicate support material;
(d) separating solids from the slurry and washing said solid
composition with solvent to remove any traces of free manganese
(II) salts; and
(e) drying the solid composition to remove solvent and
moisture.
10. A process according to claim 9 wherein the aluminosilicate
support material is a zeolite.
11. A process according to claim 9 wherein the aluminosilicate
support material has a pore size from about 3 to 10 Angstroms.
12. A process according to claim 9 wherein the aluminosilicate
support material is silicoalumino phosphate.
13. A process according to claim 9 wherein the peroxy compound is
sodium perborate.
14. A process according to claim 9 further comprising an inorganic
phosphate salt stabiizer in an amount from about 5 to 35% by weight
of the total composition.
15. A process according to claim 14 wherein the phosphate
stabilizer is chosen from the group consisting of tripolyphosphate,
orthophosphate, pyrophosphate and mixtures thereof.
16. A process according to claim 9 wherein the solvent is
water.
17. A method for bleaching a substrate comprising placing the
substrate into water and treating with a composition
comprising:
(a) a peroxy compound present in an amount to deliver at least 30
mg active oxygen per liter to the wash solution; and
(b) a bleaching catalyst which delivers at least 0.5 ppm manganese
(II) cation per liter was solution, said catalyst comprising an
aluminosilicate support material whereon is adsorbed a
water-soluble manganese (II) salt and a salt of a divalent metal
cation selected from magnesium or zinc;
the weight ratio of manganese (II) to divalent metal cation being
from about 1:20 to 20:1, the ratio of divalent metal cation to
aluminosilicate support material being from about 1:1000 to
1:10.
18. A method according to claim 17 further comprising an inorganic
phosphate salt stabilizer present in an amount to deliver from
about 0.05 to 0.30 grams per liter wash solution.
19. A method according to claim 18 wherein the phosphate salt is
selected from the group consisting of tripolyphosphate,
orthophosphate, pyrophosphate and mixtures thereof.
20. A method according to claim 17 wherein the peroxy compound is a
sodium perborate salt.
21. A method according to claim 17 wherein the composition further
comprises from 1 to 98% of laundry detergent adjuncts selected from
the group consisting of surfactants, builders, fabric softeners,
enzymes, inorganic fillers, colorants, lather boosters and mixtures
thereof.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a bleach catalyst, processes for its
preparation and bleaching compositions incorporating this
catalyst.
2. The Prior Art
Dry bleaching powders, such as those for cleaning laundry,
generally contain inorganic persalts as the active component. These
persalts serve as a source of hydrogen peroxide.
Normally, persalt bleach activity in aqueous solution is
undetectable where temperatures are less than 100.degree. F. and
delivery dosages less than 100 ppm active oxygen. The art has
recognized, however, that bleaching under mild conditions may be
effectuated through the use of activators.
U.S. Pat. No. 3,156,654 discloses heavy metal ions such as cobalt
in combination with chelating agents to catalyze peroxide
decomposition. U.S. Pat. No. 3,532,634 suggests a similar approach
but with cations that are transition metals having atomic number 24
to 29. Neither system is totally satisfactory.
Bare metal ions, even when chelated, accelerate wasteful
decomposition reactions that are non-bleach effective. Under
alkaline conditions, as with laundry cleaning compositions, metal
ions undergo irreversible oxidation. Perversely, the peroxide
bleaching reaction is most effective at high pH. Furthermore, the
prior art metal ion catalysts are sensitive to water hardness.
Their activity varies with the calcium and magnesium content of the
water source.
Manganese (II) salts have been reported to be exceptionally
effective in activating persalts under mild conditions. European
patent application No. 0 082 563 discloses bleach compositions
containing manganese (II) in conjunction with carbonate compounds.
British patent application No. 82 36,005 describes manganese (II)
in conjunction with a condensed phosphate/orthophosphate and an
aluminosilicate, the builder combination enhancing bleach
performance.
The aforementioned compositions stil suffer from the presence of
soluble manganese (II) ions. When utilized for whitening laundry,
the soluble ions deposit on fabrics. Strong oxidants, such as
hypochlorites, are frequently included in laundry washes. Deposited
manganese will react with strong oxidants to form highly staining
manganese dioxide.
European patent application No. 0 025 608 reveals to peroxide
decomposition catalyst consisting of zeolites or silicates whose
cations have been exchanged for heavy metals such as manganese.
Co-pending U.S. application Ser. No. 597,971, now U.S. Pat. No.
4,536,183 discloses a bleach activator comprising a water-soluble
manganese (II) salt adsorbed onto a solid inorganic silicon support
material, the combination having been prepared at a pH from 7.0 to
11.1. Although these systems provide adequate bleaching, more
potent catalysts would be desirable where the amount of catalyst
must be kept at a low level. Economics, peroxide stability,
compatibility and environmental considerations encourage use of
activator systems with the highest possibe activity.
U.S. Pat. No. 4,208,295 (Sai et al.) discloses bleaching detergent
compositions wherein water-insoluble aluminosilicates have had
their cations partially exchanged with calcium or magnesium ions.
Incorporation of calcium and magnesium was found to improve the
storage stability of sodium percarbonate. Evidently, these
particular divalent cations were not considered as bleach
accelerators but, rather, as stabilizers to prevent decomposition
of peroxide.
Consequently, it is an object of the present invention to provide a
bleaching composition containing a persalt and a manganese bleach
catalyst that will not result in substrate staining.
A further object of this invention is to provide a nonstaining
bleach composition exhibiting exceptionally high bleach
performance.
Another object of this invention is to provide a process for the
preparation of manganese bleach catalysts.
SUMMARY OF THE INVENTION
A bleaching composition is provided comprising a peroxy compound
and a peroxide catalyst comprising an aluminosilicate support
material whereon is adsorbed a water-soluble manganese (II) salt
and a salt of a divalent metal cation selected from magnesium or
zinc, the weight ratio of manganese (II) to divalent metal cation
being from about 1:20 to 20:1, the ratio of divalent metal cation
to aluminosilicate support material ranging from about 1:1000 to
1:10, and the weight ratio of catalyst to peroxy compound being
from about 1:100 to 1:1.
Furthermore, a process for the preparation of a catalyst for the
controlled decomposition of peroxy compounds is disclosed
comprising:
(a) dissolving a water-soluble salt of manganese (II) and of a
divalent metal cation selected from magnesium or zinc, in a solvent
and therein suspending an aluminosilicate support material to form
a slurry, the weight ratio of divalent metal cation to the
aluminosilicate ranging from 1:1000 to 1:10 and of manganese (II)
to divalent metal cation ranging from about 1:20 to 20:1;
(b) adjusting pH to achieve a value from about 7.0 to 11.1;
(c) agitating the slurry mixture of divalent metal salt and a
luminosilicate support material;
(d) separating solids from the slurry and washing said solid
composition with solvent to remove any traces of free manganese
(II) salts; and
(e) drying the solid composition to remove solvent and
moisture.
DETAILED DESCRIPTION OF THE INVENTION
It has been found that a highly effective bleaching catalyst is
obtained by treatment of an aluminosilicate support material with a
divalent magnesium or zinc salt in conjunction with a manganese
(II) salt. This mixed metal impregnated aluminosilicate catalyst is
an impovement over the aluminosilicate containing only adsorbed
manganese (II) cations which is reported in co-pending U.S.
application Ser. No. 597,971, herein incorporated by reference.
Moreover, the mixed metal catalyst still maintains all the
desirable features of the single metal impregnated catalyst. For
instance, the problem of staining is still avoided. The problem
arises when fabrics are laundered in the presence of free manganese
cations. Some of these cations deposit onto the fabric. Subsequent
laundering in the presence of strong oxidants, e.g. sodium
hypochlorite, converts the deposited cations into colored manganese
dioxide. Stains are thereby formed.
Cations such as iron, copper and calcium when used as replacements
for mangesium or zinc no activity improvement over non-treated
aluminosilicate support material having manganese (II) adsorbed
thereon.
The manganese used in the present invention can be derived from any
manganese (II) salt which delivers manganous ions in aqueous
solution. Manganous sulfate and manganous chloride or complexes
thereof, such as manganous triacetate, are examples of suitable
salts.
The aluminosilicate support material is preferably of a pore size
of from 3 to 10 Angstroms, more preferably from 3 to 5
Angstroms.
Zeolites, in powder form, are the preferred support materials,
especially where the composition is intended for laundering
clothes. Amorphous aluminosilicates are, however, also suitable as
support materials. Many commercial zeolites have been specifically
designed for use in laundering applications. Accordingly, they
exhibit the favorable properties of dispersivity in wash solution.
Moreover, their tendency for being entrapped by fabrics is low.
Synthetic zeolites are preferred over the natural ones. The latter
have an appreciable content of extraneous metal ions that may
promote wasteful peroxide decomposition reactions. Illustrative of
commercially available zeolites falling within the scope of this
invention are the 4A and 13X type sold by Union Carbide under the
designation ZB-100 and ZB-400, respectively. ZB-100 has an average
pore size of 4 Angstroms. ZB-400 has an average pore size of 10
Angstroms.
Another type of suitable support material is the silicoalumino
phosphates (SAPOs). These materials are also commercially available
from Union Carbide. SAPOs have a wide range of compositions within
the general formula 0-0.3R(Si.sub.x Al.sub.y P.sub.z)O.sub.2 where
x, y and z represent the mole fractions of Si, Al and P,
respectively. The range for x is 0.01 to 0.98, for y from 0.01 to
0.60, and for z from 0.01 to 0.52. R refers to the organic template
that is used to develop the structure of the particular SAPO.
Typical templates used in preparing SAPOs are organic amines or
quaternary ammonium compounds. Included within the SAPO family are
structural types such as AlPO.sub.4 -16, Sodalite, Erionite,
Chabazite, AlPO.sub.4 -11, Novel, AlPO.sub.4 -5 and Faujasite.
Finished catalyst will contain from about 0.1% to about 5.5% (II)
per weight of solid support. Preferably, the amount of manganese
(II) is from about 1 to about 2.5%.
The catalyst and compositions of this invention may be applied to
hard substrates such as dentures, bathroom tiles, toilet bowls and
ceramic floors. Flexible substrates, specifically laundry, will,
however, be focused upon in the subsequent discussion.
Laundry bleach compositions of this invention comprise, besides the
mixed metal catalyst, a peroxide source and a phosphate stabilizer.
Suitable peroxy compounds include the inorganic persalts which
liberate hydrogen peroxide in aqueous solution. These may be
water-soluble perborates, percarbonates, perphosphates,
persilicates, persulfates and organic peroxides. Amounts of peroxy
compound in the dry bleach powder should range from about 5 to
about 30%. At least 30 ppm active oxygen should be delivered by the
persalt to a liter of wash water. For instance, with sodium
perborate monohydrate, this represents a minimum amount of 200 mg
per liter of wash water.
The catalyst should deliver a minimum level of 0.5 ppm manganese
(II) ion to the wash. For instance, if a catalyst has 1 weight % of
manganese then at least 5 grams catalyst per liter of wash solution
is required.
The ratio of active oxygen generated by peroxy compound to
manganese (II) ion in aqueous solution ranges from about 1000:1 to
1:1000, preferably 1000:1 to 1:10.
Phosphate stabilizers are suggested for combination with the dry
bleach powders. Suitable stabilizers include the alkali metal salts
of tripolyphosphate, orthophosphate and pyrophosphate. Amounts of
phosphate stabilizer should range from about 5% to about 35%.
Preferably, they should be present from about 10% to 15%. In
aqueous solution, the phosphate stabilizer level should be at least
10 ppm, the ratio of stabilizer to peroxy compound being from about
10:1 to 1:10.
Surface active detergents may be present in an amount from about 2%
to 50% by weight, preferably from 5% to 30% by weight. These
surface active agents may be anionic, nonionic, zwitterionic,
amphoteric, cationic or mixtures thereof.
Among the anionic surfactants are water-soluble salt of
alkylbenzene sulfonates, alkyl sulfates, alkyl ether sulfates,
paraffin sulfonates, .alpha.-olefin sulfonates,
.alpha.-sulphocarboxylates and their esters, alkyl glycerol ether
sulfonates, fatty acid monoglyceride sulfates and sulfonates, alkyl
phenol polyethoxy ether sulfates, 2-acyloxy-alkane-1-sulfonates and
.beta.-alkoxyalkane sulfonates. Soaps are also preferred anionic
surfactants.
Nonionic surfactants are water-soluble compounds produced by the
condensation of ethylene oxide with a hydrophobic compound such as
alcohol, alkyl phenol, polypropoxy glycol or polypropoxy ethylene
diamine.
Cationic surface active agents include the quaternary ammonium
compounds having 1 to 2 hydrophobic groups with 8-20 carbon atom,
e.g., cetyl trimethylammonium bromide or chloride, and dioctadecyl
dimethylammonium chloride.
A further exposition of suitable surfactants for the present
invention appears in "Surface Active Agents and Detergents", by
Schwartz, Perry & Berch (Interscience, 1958), the disclosure of
which is incorporated herein by reference.
Detergent builders may be combined with the bleach compositions.
Useful builders can include any of the conventional inorganic and
organic water-soluble builder salts. Typical of the well known
inorganic builders are the sodium and potassium salts of the
following: pyrophosphate, tripolyphosphate, orthophosphate,
carbonate, bicarbonate, silicate, sesquicarbonate, borate and
aluminosilicate. Among the organic detergent builders that can be
used in the present invention are the sodium and potassium salts of
citric acid and nitrilotriacetic acid. These builders can be used
in an amount from 0 up to about 80% by weight of the composition,
preferably from 10% to 50% by weight.
Apart from detergent active compounds and builders, compositions of
the present invention can contain all manner of minor additives
commonly found in laundering or cleaning compositions in amounts in
which such additives are normally employed. Examples of these
additives include: lather boosters, such as alkanolamides,
particularly the monoethanolamides derived from palm kernel fatty
acids and coconut fatty acids; lather depressants, such as alkyl
phosphates, waxes and silicones; fabric softening agents; fillers;
and usually present in very minor amounts, fabric whitening agents,
perfumes, enzymes, germicides and colorants.
The following examples will more fully illustrate the embodiments
of the invention. All parts, percentages and proportions referred
to herein and in the appended claims are by weight unless otherwise
indicated.
EXAMPLE 1
A vessel was charged with 125 grams zeolite (ex. Union Carbide
ZB-100) and approximately 100 ml deionized water. The pH of this
slurry was lowered to 9.5 with 1N hydrochloride acid. Hydrated
magnesium chloride, 20.3 grams, was dissolved in water and added to
the zeolite slurry. For about 20 minutes the zeolite slurry was
stirred with the magnesium salt. Approximately 0.8 millequivalent
hydrated magnesium chloride was employed per gram of zeolite
support.
Subsequent to this treatment, 5 grams manganese chloride was added
to the slurry and the mixture agitated for an additional 20
minutes. Solids were then filtered and washed with sufficient water
to remove any unadsorbed manganese. The catalyst was then
dried.
Several methods of drying the catalyst may be employed. In one
method, the catalyst is contacted with a volatile water miscible
organic solvent (bp<60.degree. C.) below the solvent's boiling
point to remove moisture through dissolution. Acetone or methanol
are suitable solvents. A more economical drying process utilizes
heat. Normally, temperatures below 130.degree. C. are applied to
the catalyst. Higher temperatures, up to 350.degree. C., are also
suitable provided the residence time of the catalyst in the drier
is less than 5 minutes.
EXAMPLE 2
A bleach composition was formulated comprising:
______________________________________ Component Weight (grams)
______________________________________ Sodium carbonate 1.00 Sodium
tripolyphosphate 0.31 Sodium perborate monohydrate 0.31
Manganese/zeolite bleach activator --
______________________________________
Bleaching tests were conducted with a four pot Tergotometer
apparatus from the U.S. Testing Company. Wash solutions were
prepared from deionized water of 12.degree. French hardness (Ca/Mg
2:1). Solutions were raised to pH of about 10.9 by addition of 4 ml
of 1N sodium hydroxide. Wash volumes were 1 liter. Temperature was
maintained at 100.degree. F. Agitation was provided throughout a 20
minute wash period.
Bleach activity was determined by measuring the change in
reflectance (.alpha.R) of a dry cotton cloth (4".times.6"). Prior
to bleaching, the cloth was uniformly stained with a tea solution
and washed several times in a commercial detergent. Reflectance was
measured on a Gardner XL-23 reflectometer.
Varying amounts of bleach catalyst were added to the aforementioned
bleach composition. Catalysts were prepared according to Example 1,
except that manganese chloride amounts were altered to provide a
range of metal concentration as outlined in Table I. The control
catalyst was also prepared in the manner outlined in Example 1
except that the zeolite was not treated with magnesium chloride.
Higher reflectance changes signify greater bleach
effectiveness.
Table I outlines the performance of various total catalyst levels
and differing amounts of manganese adsorbed thereon. For instance,
0.2% Mn represents a zeolite treated with 0.2% manganese
chloride.
TABLE I ______________________________________ Set A (Control)
.DELTA.R Weight of Manganese Catalyst Absent Magnesium Treatment
Catalyst (gram) .2% Mn .4% Mn .6% Mn .9% Mn
______________________________________ 0.0 4.3 3.8 4.8 3.7 0.08 4.8
3.9 4.2 7.2 0.13 4.9 5.5 5.6 8.8 0.16 4.7 5.3 8.5 8.2 0.22 5.8 6.1
7.9 9.5 0.30 6.0 7.6 8.6 9.6 ______________________________________
Set B .DELTA.R Weight of Manganese Catalyst With Magnesium
Treatment Catalyst (gram) .2% Mn .4% Mn .9% Mn
______________________________________ 0.0 4.4 3.7 3.6 0.08 6.8
10.4 9.3 0.13 7.4 10.9 12.6 0.16 7.7 10.2 14.6 0.22 10.0 11.9 13.8
0.30 9.8 14.6 14.5 ______________________________________
Table I demonstrates that when manganese is adsorbed onto zeolite,
the resulting solid can accelerate the bleaching from peroxide
solutions. Furthermore, the mixed metal catalyst under Set B, Table
I, is shown to provide substantially better bleaching than
non-treated Set A. In Set B, the zeolite has been treated with both
magnesium and manganese. The mixed metal catalyst has a greater
.alpha.R than non-treated manganese on zeolite at each level of
catalyst weight investigated.
EXAMPLE 3
Herein illustrated are the effects of divalent metal cations other
than magnesium on the bleach activity of a manganese impregnated
zeolite. Catalysts were prepared according to Example 1, except for
substitution of magnesium with the hereinbelow stated divalent
metals and corresponding changes in their employed weights. The
alternate salts evaluated were zinc chloride, calcium chloride,
copper sulphate and iron nitrate.
Catalysts were incorporated into a bleach composition with the
following formulation:
______________________________________ Component Weight (grams)
______________________________________ Sodium carbonate 0.5 Sodium
tripolyphosphate 0.1 Sodium perborate monohydrate 0.3 Nonionic
surfactant 0.15 Manganese/Zeolite bleach activator --
______________________________________
Bleaching tests were conducted as described in Example 2. Results
for these tests are outlined in Table II.
TABLE II ______________________________________ Mixed Metal
Catalyst Bleach Performance .DELTA.R Weight of Control* 2% 2%
Catalyst (grams) 0.5% Mn only ZnCl.sub.2 CaCl.sub.2 2% MgCl.sub.2
______________________________________ 0.0 0.69 2.32 1.01 0.50 0.05
2.80 3.10 1.36 2.90 0.10 3.64 4.60 2.79 4.21 0.15 4.31 4.07 3.06
4.6 0.20 4.48 5.50 3.72 5.50 0.25 4.40 5.09 4.65 6.03
______________________________________ *0.5% (manganese on zeolite)
with other columns indicating additional amounts and type of second
metal salt impregnated alongside manganese ions.
The results listed in Tables I and II demonstrate that the presence
of zinc or magnesium salt along with manganese on the zeolite
catalyst improves bleaching relative to that of a purely manganese
impregnated substrate. Calcium, copper and iron salts when combined
with manganese on the catalyst retard the bleach performance
relative to the control material.
The foregoing description and examples illustrate selected
embodiments of the present invention and in light thereof
variations and modifications will be suggested to one skilled in
the art, all of which are in the spirit and purview of this
invention.
* * * * *